The present invention relates to industrial clamps having at least one pivotal arm.
FIG. 1 is a perspective view of a typical valve and cylinder system 8 which is common in the art of industrial clamps. In particular, there is a hollow cylinder 10 having a first end 14 and a second end 16. Within the cylinder 10, there is a piston (not shown) which is movable between a first end position and a second end position. The piston is connected to a rod 12 that protrudes through the second end 16. The rod 12 is typically connected to a linkage assembly (not shown) to which a shaft (not shown) is rotatably connected. A clamp arm (not shown) is then typically fixedly mounted on the shaft.
At or near both the first end 14 and the second end 16 of the cylinder 10 are two proximity switches 18. These two proximity switches 18 serve to provide an indirect indication of the rotational position of the clamp arm by detecting whether the piston (or rod 12) is at the first end position (retracted position) or the second end position (extended position). Typically, the cylinder 10, in combination with the proximity switches 18, requires one or more electrical power and/or control cables 19.
The rod 12 and the piston (not shown) together define a full bore area (not shown) and an annulus area (not shown) on opposite sides of the piston within the cylinder 10. From the full bore and annulus two areas within the cylinder 10, a first air line 20 and a second air line 22 are routed to an air valve system 24 which is located remote from the cylinder 10.
The air valve system 24 typically has one or more exhaust ports in which one or more silencers 26 are fitted. In addition, the air valve system 24 typically has a main pneumatic air supply line 28 and an electrical power and/or control cable 30.
The typical valve and cylinder system 8, as described above, has certain drawbacks. First, for example, the remote location of the air valve system 24 from the cylinder 10 can create undesired difficulties if local control of the cylinder 10 and the associated clamp arm is desired. Second, the remote location of the air valve system 24 from the cylinder 10 also, in many instances, unnecessarily dictates the combined need for a multiplicity of electrical power and/or control cables and air lines at the two separate locations. The unnecessary multiplicity of electrical power and/or control cables can be especially troublesome in a manufacturing environment wherein many clamps are used simultaneously. Third, the remote location of the air valve system 24 from the cylinder 10 also unnecessarily creates additional problems for the combined servicing and repair of the cylinder 10 and the air valve system 24 at the two separate locations. Fourth, the remote location of the air valve system 24 from the cylinder 10 uses only approximately 20% of the compressed air in the system 8.
Thus, there is a present need in the art for eliminating the drawbacks and problems associated with the cylinder and the air valve system being at locations which are remote from each other.
In a clamp having at least one clamp arm moveable between a clamped position and a released position in response to movement of an actuator between first and second end limits of travel, the present invention provides means for selectively setting at least one of the clamped position and the released position at an actuator position between the first and second end limits of travel of the actuator.
In a clamp having at least one clamp arm moveable between a clamped position and a released position in response to movement of an actuator between first and second end limits of travel, the present invention provides means for selectively controlling a speed of actuator movement as the actuator moves between the first and second end limits of travel. Preferably, the present invention further provides means for selectively controlling the speed of actuator movement as the actuator approaches at least one of the first and second end limits of travel to provide a soft touch clamp action.
In a clamp having at least one clamp arm moveable between a clamped position and a released position in response to movement of an actuator controlled by differential fluid pressure in first and second chambers located on opposite sides of the actuator, the present invention provides means for selectively adjusting pressurized fluid within the first and second chambers independent of one another.
In a clamp network system having a plurality of clamps actuated in response to pressurized fluid, the present invention provides each of the plurality of clamps with a separate valve and position control system.
The present invention also provides a valve and position control system which is integrable with an industrial clamp. The valve and position control system, according to the present invention, is integrable with a clamp which has a main housing, a hollow cylinder having a first end and a second end mounted within the main housing, and a piston movable between a first end position and a second end position within the hollow cylinder. The clamp further includes a rod connected to the piston and protruding from the second end of the hollow cylinder, defining a full bore area and an annulus area on opposite sides of the piston within the hollow cylinder. In addition, the clamp includes a linkage assembly coupled to the rod and mounted within the main housing, a shaft rotatably connected to the linkage assembly, a clamp arm fixedly mounted on the shaft outside of the main housing, means for sensing the position of the clamp arm, and means for sensing the air pressure within the hollow cylinder. The valve and position control system, according to the basic embodiment of the present invention, is intended to be integrable with this type of clamp.
In a basic embodiment of the present invention, the integrable valve and position control system includes a complementary housing which is integrable with the main housing of the clamp. This complementary housing has an air supply port, an exhaust port, and an electronic interface port. In addition, the integrable valve and position control system includes a first direction control valve having three ports and two positions. This first direction control valve is capable of selectively and pneumatically connecting the full bore area of the hollow cylinder to one of either the air supply port or the exhaust port. The first direction control valve is mounted within the complementary housing. In addition to the first direction control valve, the integrable valve and position control system also includes a second direction control valve having three ports and two positions. This second direction control valve is capable of selectively and pneumatically connecting the annulus area of the hollow cylinder to one of either the air supply port or the exhaust port. The second direction control valve is mounted within the complementary housing.
According to the basic embodiment of the present invention, the integrable valve and position control system also includes first means for pneumatically piloting the first direction control valve. This first pneumatic piloting means is mounted within the complementary housing. In addition to the first pneumatic piloting means, the integrable valve and position control system also includes second means for pneumatically piloting the second direction control valve. This second pneumatic piloting means is also mounted within the complementary housing.
Further according to the basic embodiment of the present invention, the integrable valve and position control system also includes an electronic control circuit mounted within the complementary housing. This electronic control circuit is electrically connected to the first pneumatic piloting means, the second pneumatic piloting means, and the electronic interface port. In addition, this electronic control circuit is also electrically connectible to the clamp arm position sensing means and to the air pressure sensing means.
According to the basic embodiment of the present invention, the first pneumatic piloting means preferably includes a first solenoid direction control valve having three ports and two positions. This first solenoid direction control valve selectively and pneumatically connects the first direction control valve to one of either the air supply port or the exhaust port to pilot the first direction control valve. In addition, the second pneumatic piloting means preferably includes a second solenoid direction control valve having three ports and two positions. This second solenoid direction control valve selectively and pneumatically connects the second direction control valve to one of either the air supply port or the exhaust port to pilot the second direction control valve. In this way, the first direction control valve and the second direction control valve are each piloted independently.
Further according to the basic embodiment of the present invention, the integrable valve and position control system also preferably includes means for metering out air from the hollow cylinder. This metering out means is mounted within the complementary housing and preferably includes first means for metering out air from the full bore area of the hollow cylinder and into the first direction control valve, and preferably includes second means for metering out air from the annulus area of the hollow cylinder and into the second direction control valve. The first metering out means preferably includes a first flow control valve and a first non-return check valve pneumatically connected in parallel, and the second metering out means preferably includes a second flow control valve and a second non-return check valve pneumatically connected in parallel.
Still further according to the basic embodiment of the present invention, the complementary housing preferably includes a plurality of compartments, wherein the electronic control circuit is situated in one of the compartments, and wherein the first directional control valve and the second directional control valve are situated in another one of the compartments. Preferably, at least some of the compartments are detachable from at least one of the main housing and the complementary housing.
Finally according to the basic embodiment of the present invention, the integrable valve and position control system also preferably includes a silencer fitted within the exhaust port of the complementary housing, a first exhaust restrictor pneumatically connected between the first direction control valve and the exhaust port, a second exhaust restrictor pneumatically connected between the second direction control valve and the exhaust port, first means for manually overriding the position of the first direction control valve, and second means for manually overriding the position of the second direction control valve.
In an alternative embodiment of the present invention, the integrable valve and position control system accommodates a clamp which includes neither clamp arm position sensing means nor air pressure sensing means. To be integrable with this type of clamp, according to the alternative embodiment of the present invention, the integrable valve and position control system includes a complementary housing which is integrable with the main housing of the clamp. This complementary housing has an air supply port, an exhaust port, and an electronic interface port. In addition, the integrable valve and position control system includes means for sensing the position of the clamp arm, means for sensing the air pressure within the hollow cylinder, and a first direction control valve having three ports and two positions. This first direction control valve is capable of selectively and pneumatically connecting the full bore area of the hollow cylinder to one of either the air supply port or the exhaust port. The first direction control valve is mounted within the complementary housing. In addition to the first direction control valve, the integrable valve and position control system also includes a second direction control valve having three ports and two positions. This second direction control valve is capable of selectively and pneumatically connecting the annulus area of the hollow cylinder to one of either the air supply port or the exhaust port. The second direction control valve is mounted within the complementary housing.
According to the alternative embodiment of the present invention, the integrable valve and position control system also includes first means for pneumatically piloting the first direction control valve. This first pneumatic piloting means is mounted within the complementary housing. In addition to the first pneumatic piloting means, the integrable valve and position control system also includes second means for pneumatically piloting the second direction control valve. This second pneumatic piloting means is also mounted within the complementary housing.
Further according to the alternative embodiment of the present invention, the integrable valve and position control system also includes an electronic control circuit mounted within the complementary housing. This electronic control circuit is electrically connected to the first pneumatic piloting means, the second pneumatic piloting means, the electronic interface port, the clamp arm position sensing means, and the air pressure sensing means.
According to the alternative embodiment of the present invention, the first pneumatic piloting means preferably includes a first solenoid direction control valve having three ports and two positions. This first solenoid direction control valve selectively and pneumatically connects the first direction control valve to one of either the air supply port or the exhaust port to pilot the first direction control valve. In addition, the second pneumatic piloting means preferably includes a second solenoid direction control valve having three ports and two positions. This second solenoid direction control valve selectively and pneumatically connects the second direction control valve to one of either the air supply port or the exhaust port to thereby pilot the second direction control valve. In this way, the first direction control valve and the second direction control valve are each piloted independently.
Further according to the alternative embodiment of the present invention, the integrable valve and position control system also preferably includes means for metering out air from the hollow cylinder. This metering out means is mounted within the complementary housing and preferably includes first means for metering out air from the full bore area of the hollow cylinder and into the first direction control valve, and preferably includes second means for metering out air from the annulus area of the hollow cylinder and into the second direction control valve. The first metering out means preferably includes a first flow control valve and a first non-return check valve pneumatically connected in parallel, and the second metering out means preferably includes a second flow control valve and a second non-return check valve pneumatically connected in parallel.
Still further according to the alternative embodiment of the present invention, the complementary housing preferably includes a plurality of compartments, wherein the electronic control circuit is situated in one of the compartments, and wherein the first directional control valve and the second directional control valve are situated in another one of the compartments. Preferably, at least some of the compartments are detachable from at least one of the main housing and the complementary housing.
Finally according to the alternative embodiment of the present invention, the integrable valve and position control system also preferably includes a silencer fitted within the exhaust port of the complementary housing, a first exhaust restrictor pneumatically connected between the first direction control valve and the exhaust port, a second exhaust restrictor pneumatically connected between the second direction control valve and the exhaust port, first means for manually overriding the position of the first direction control valve, and second means for manually overriding the position of the second direction control valve. In addition, the clamp arm sensing means preferably includes either proximity switches, at least one rotary switch, or at least one absolute position linear sensor.
In an another embodiment of the present invention, the clamp is actually integrated with the valve and position control system to form a clamp with integrated valve and position control system. In such an another embodiment, the clamp includes an integrated housing having an air supply port, an exhaust port, and an electronic interface port. The clamp also includes a hollow cylinder having a first end and a second end mounted within the integrated housing, a piston movable between a first end position and a second end position within the hollow cylinder. The clamp further includes a rod connected to the piston and protruding from the second end of the hollow cylinder, defining a full bore area and an annulus area on opposite sides of the piston within the hollow cylinder. In addition, the clamp includes a linkage assembly coupled to the rod and mounted within the integrated housing, a shaft rotatably connected to the linkage assembly, a clamp arm fixedly mounted on the shaft outside of the integrated housing, means for sensing the position of the clamp arm, and means for sensing the air pressure within the hollow cylinder.
According to the another embodiment of the present invention, the clamp also includes a first direction control valve having three ports and two positions. This first direction control valve selectively and pneumatically connects the full bore area of the hollow cylinder to one of either the air supply port or the exhaust port. The first direction control valve is mounted within the integrated housing. In addition to the first direction control valve, the clamp also includes a second direction control valve having three ports and two positions. This second direction control valve selectively and pneumatically connects the annulus area of the hollow cylinder to one of either the air supply port or the exhaust port. The second direction control valve is mounted within the integrated housing.
Further according to the another embodiment of the present invention, the clamp also includes first means for pneumatically piloting the first direction control valve. This first pneumatic piloting means is mounted within the integrated housing. In addition to the first pneumatic piloting means, the clamp also includes second means for pneumatically piloting the second direction control valve. This second pneumatic piloting means is also mounted within the integrated housing. Further, the clamp also includes an electronic control circuit mounted within the integrated housing. This electronic control circuit is electrically connected to the first pneumatic piloting means, the second pneumatic piloting means, the electronic interface port, the clamp arm position sensing means, and the air pressure sensing means.
According to the another embodiment of the present invention, the first pneumatic piloting means preferably includes a first solenoid direction control valve having three ports and two positions. This first solenoid direction control valve selectively and pneumatically connects the first direction control valve to one of either the air supply port or the exhaust port to pilot the first direction control valve. In addition, the second pneumatic piloting means preferably includes a second solenoid direction control valve having three ports and two positions. This second solenoid direction control valve selectively and pneumatically connects the second direction control valve to one of either the air supply port or the exhaust port to pilot the second direction control valve. In this way, the first direction control valve and the second direction control valve are each piloted independently.
Further according to the another embodiment of the present invention, the clamp also preferably includes means for metering out air from the hollow cylinder. This metering out means is mounted within the integrated housing and preferably includes first means for metering out air from the full bore area of the hollow cylinder and into the first direction control valve, and preferably includes second means for metering out air from the annulus area of the hollow cylinder and into the second direction control valve. The first metering out means preferably includes a first flow control valve and a first non-return check valve pneumatically connected in parallel, and the second metering out means preferably includes a second flow control valve and a second non-return check valve pneumatically connected in parallel.
Still further according to the another embodiment of the present invention, the integrated housing preferably includes a plurality of compartments, wherein the electronic control circuit, the hollow cylinder, and the first directional control valve and the second directional control valve are situated in separate compartments. Preferably, at least some of the compartments are detachable from the integrated housing.
Finally according to the another embodiment of the present invention, the clamp also preferably includes a silencer fitted within the exhaust port of the integrated housing, a first exhaust restrictor pneumatically connected between the first direction control valve and the exhaust port, a second exhaust restrictor pneumatically connected between the second direction control valve and the exhaust port, first means for manually overriding the position of the first direction control valve, and second means for manually overriding the position of the second direction control valve. In addition, the clamp arm sensing means preferably includes either proximity switches, at least one rotary switch, or at least one absolute position linear sensor.
Other objects, advantages and applications of the present invention will become apparent to those skilled in the art when the following description of the best mode contemplated for practicing the invention is read in conjunction with the accompanying drawings.